GREENVILLE — Greenville High coach Jeremy Williams wears two different types of microphones during his team’s football games.

The first is a headset, neatly tucked under the coach’s baseball cap. It’s not for communication with other coaches, but rather to amplify the words out of Williams’ mouth. His once-powerful voice has been reduced to nearly whispers in recent months because of symptoms of ALS, or Lou Gehrig’s disease. The headset is wired to a speaker-like box tied around the dwindling waist of the coach.

The second one is a tiny wireless microphone that Williams wears near the collar of his shirt. It picks up the coach’s words for the documentary “Season of a Lifetime,” which is based on Williams and his inspirational attitude toward the terminal illness. (For more information on the documentary, go to www.seasonofalifetime.tv.)

Atlanta filmmaker Rick Cohen and his crew have been following Williams since April.

“This is the true story of a high school football coach who unselfishly prayed for adversity to help improve his team and received it in the form of ALS,” Cohen said, explaining his appeal to the project.

“Through Jeremy’s beliefs, his trust and his faith, he’s convinced the illness is a blessing not a curse — a direct message from God. To Jeremy, his illness is a way to reach out to his players with challenging family situations, to help mend the once-racially divided town, and to encourage his son stricken with spina bifida — and in an amazing way for the rest of the world to see.”

“The message is clear — we are not promised one more day here on earth, so make the most of every day and make a difference.”

Cohen, 45, is an independent filmmaker with Endorphin Entertainment and an executive producer with Fisheye Media Productions, the two Atlanta-based companies that have partnered to produce “Season of a Lifetime.” Since last spring, Cohen has made nearly 30 trips to Greenville (located in Meriwether County in west central Georgia) to film segments of Williams with his players, family members, former college teammates, church family and others.

The plan is to film Williams and the Patriots until the end of this season. Said Cohen, “As far as they go, that’s where this marvelous journey will end. If it’s the first round of the playoffs, so be it. If it’s the Georgia Dome [for the state championship], then God willing.”

After the season, Cohen will huddle in the studio for three months of postproduction, with the hope of turning out a rough draft of the documentary by March. “Season of a Lifetime” will be entered in several film festivals in late 2011 in an attempt to attract a distribution deal to release it in theaters for 2012.

Cohen became interested after reading last year’s media accounts of the frail coach leading Greenville to an undefeated regular season, losing to the eventual state champions in the second round of the playoffs.

Through mutual friends, Cohen arranged a meeting with Williams in January. Other filmmakers, including representatives from HBO and ESPN, had expressed interest in telling the story.

“Why give this story to you?” Williams asked.

“Have any of these so-called big boys come down to visit you in Greenville?” Cohen replied.

Williams shook his head “no.”

“Well, then I guess they don’t want to tell your story as bad enough as we do,” Cohen said, causing both men to share a laugh.

Williams said he eventually agreed to participate in the documentary “to do a true account of how God has affected our team in a very positive way.”

The coach’s health has worsened in recent months. He is wearing a feeding tube while he sleeps at night. He wears the voice amplifier so others can hear him speak throughout the day. During games, Williams moves around the field in a motorized wheelchair. It is a long way from last season, when he insisted on standing on the sidelines.

“Jeremy is in good spirits … he is in the midst of where he loves to be — and that’s around 45 players during football season,” said his wife, Jennifer Williams.

Williams and his team barely noticed when three cameras focused on them in a victory against Macon County a couple of weeks ago.

“Everybody is used to it, well except for the freshmen,” Greenville quarterback Mario Alford said with a laugh. “Those freshmen, they try to get in front of the camera at every opportunity.”

After Alford ran for a touchdown in Greenville’s 41-12 win over Macon County, Williams motioned for his quarterback by nodding his head up and down. Alford took a knee by the side of the wheelchair and put his arm around the coach as the two shared a smile.

“We all want to win for coach,” Alford said. “He’s a big inspiration, not only for our football team, but also the entire community.

“It’s a good thing that this movie is being made because a lot of other people will be able to see what a great man he is.”